1. Field of the Invention
The present invention relates to an inkjet printing head cleaning device and the cleaning method thereof, more particularly to an inkjet printing head using the image capturing unit to capture the image of the inkjet print head, in order to control the of the micro disturbance state at real time, and in order to compensate the variation of the inkjet print head.
2. Description of the Prior Art
The industrial inkjet printing technology can be used for manufacturing the TFT transistor, the 3D printer, the solar cell electrode, and biomedical chip enzyme printing process etc. At present, the inkjet print head should be cleaned and calibrated before printing. How to maintain fully printing function after the rest of inkjet print head for a certain time has become an important research topic of the printing process. Recently, the advanced development of 3D printing technology has been considered as the third industrial revolution by the US President Obama. Except depending on the advancement of material science, the development of 2D or 3D printing technology should be focused on the driving technology of the inkjet print head, in order to obtain good printing quality.
Regarding the driving method for cleaning the inkjet print head at present, the amplitude of driving voltage is changed to control the deformation of piezoelectric film in the inkjet print head mainly. Through the micro disturbance behavior of the piezoelectric film, the ink in nozzle will not be solidified even the inkjet print head is at the rest state, so that the nozzle crimp will not be occurred.
At present, there is no good solution for the best micro disturbance driving waveform of the inkjet print head. The problems derived from current technology are:
(1) If the driving voltage is too large, the piezoelectric behavior will be generated to form the droplet, which will cause the waste of materials.
(2) If the driving voltage is too small, it will be unable to know the state of nozzle plate.
(3) If the driving voltage is small and the frequency is high, the droplet will probably be squeezed to form the unnecessary waste. (4) The best waveform will be changed due to the variation of inkjet print head during printing process.
The driving technology of the inkjet print head associated with different ink viscosity and printing characteristics has been developed to a certain degree. When the pre-printing material is filled in the inkjet print head for heating, the ink solidification or the nozzle crimp may be occurred due to uneven heating or ink characteristics. How to keep ready ink in the nozzle has become an important research topic of the printing process.